Furnace



May 30, 1939. JIA. LINDSAY FURNACE Filed June 7, 1937 2 Sheets-Sheet 1 6 7 7 r. 5 W 223 2 W 3 M w 2 M; m 5 i 3% v G a d 2 7? V 2 MN 1 Ja'memi A);

May 30, 1939. J. A. LINDSAY FURNACE Filed June 7,

19:57 2 Sheets-Sheet 2 ZSnventor Jay/a5 14.4 #70190 Patented May 30, 1939 UNITED STATES PATENT OFFiCE 5 Claims.

This invention relates to a hot air furnace and one object of the invention is to provide a furnace wherein the hot products of combustion pass upwardly through a space or chamber about a drum through which air passes to distributing pipes, means being provided for cleaning walls of this chamber and thoroughly removing soot and the like without dismantling the furnace.

Another object of the invention is to provide cleaning means so constructed that it may be mounted upon the inner drum through which the air passes and have cleaning engagement with walls of the passage for products of combustion when the inner drum is turned about its vertical axis.

Another object of the invention is to provide improved means for imparting turning movement to the inner drum, the said means being so constructed that an actuating shaft thereof is located over the head of the furnace where it can be easily reached when it is desired to turn the drum.

Another object of the invention is to so construct the furnace that when the inner drum is turned to cause removal of soot and other dirt from the outer walls of the passage for products of combustion, the dirt will be delivered into a box which is removably mounted so that the dirt may be easily disposed of.

Another object of the invention is to provide a furnace wherein the rotatable inner drum carries circumferentially extending rings or flanges serving as supports for certain of the cleaning members and also as baffles for directing prodnets of combustion through the space about the drum.

Another object of the invention is to provide a furnace which is of comparatively simple construction, very easy to operate and. not liable to get out of order.

The invention is illustrated in the accompanying drawings, wherein:

Figure 1 is a perspective view of the improved furnace with portions in section.

Figure 2 is a sectional view taken vertically through a portion of the furnace, the view being taken along the line 2-2 of Figure 5.

Figure 3 is a perspective view of one of the cleaning members.

Figure 4 is a sectional view upon an enlarged scale taken through a joint adjacent the upper and lower ends of the furnace or drum.

Figure 5 is a top plan view of the furnace.

Figure 6 is a sectional View taken diametrically through the upper portion of the furnace.

Figure 7 is a sectional view taken transversely through the furnace along the line 1'| of Figure 1.

This improved furnace is provided with an inner drum I enclosed in an inner shell 2 which in its turn is enclosed in an outer shell or jacket 3. At its upper end the drum l is formed with an upstanding neck 4 surrounded by a sleeve 5 carried by the depending wall 6 of a cap or head I which rests upon the top of the inner shell 2 and may be secured thereto in any desired manner. This wall of the cap is also united to the upper end of the outer shell 3, and upon referring to Figure 2 it will be seen that the cap is formed with lower openings 8 establishing communication between the interior of the cap and the space between the inner and outer shells. Upper openings 9 are formed through the cap above the outer shell through which air may pass into air pipes l leading to places where the air is to be delivered. It will be understood that a pipe I0 is provided for each discharge opening 9. The space between the inner and outer shells constitutes an air passage while the space between the drum and the inner shell serves as a passage for hot products of combustion. The products of combustion must be prevented from becoming mixed with air in the drum or the air passing through the outer air space, and in order to do so the neck 4 carries at its upper end an outstanding flange H which overhangs the sleeve and carries a depending annular lip [2 which engages in a channel defined by the sleeve and the wall of the cap and at its lower end carries a resilient sealing ring l3. Ring I3 is so constructed that its free side, or inside edge, presses against the bottom of the channel or flange M. Ring l3 acts as a check valve for the sand, or similar material which fills the channel. Under ordinary running conditions this granular material or sand which fills said channel forms the air and gas-tight joint. The ring l3 only comes into play in case of an explosion, and holds the sand in the groove so that it will not be blown out and lose its capacity as an air-tight seal.

The lower base section iii of the inner drum l is sealed at ll in the same manner as described in the above paragraph. Within the base section is mounted air moistening means consisting of porous pad 18 of spun glass or the like held between upper and lower sheets of woven wire fabric 19. This air moistening partition is moistened by water sprayed upwardly from a spraying nozzle 20 carried by a water pipe 2! and it will be readily understood that air passing upwardly through the partition will take up moisture. This will prevent the hot air delivered from the drum from being too dry and also permit air to be cooled during hot weather and delivered through the pipes II] to cool a building. Air is fed into the drum through a pipe 22 which has one end secured through an opening formed in the base section, as shown in Figure 2, and referring to this figure it will be seen that this pipe extends through the inner and outer shells and is formed with an upper opening establishing communication with the outer air space between the shells, a deflector 23 being provided so that a portion of the air passing through the pipe will be directed upwardly into the outer air space, and in sum mer, deflector 23 may be shut tight so as to direct all air through drum l to be cooled. A fire box 24 extends forwardly from the lower portion of the outer shell and. in order to feed fuel to the fire in the fire box there has been provided a stoker 25, although any other suitable means of firing may be used. The fire box communicates with the lower portion of the heating chamber formed about the central air chamber by the drum l and the inner shell 2, and in order to cause the hot products of combustion to follow a tortuous path upwardly through the heating chamber there have been provided baffles in the form of rings 26 carried'by the drum. Each ballle is formed with a space through which the products of combustion pass, and upon referring to Figures 1 and 2 it will be seen that the spaces are located at opposite sides of the furnace from each other. Therefore, the products of combustion when passing upwardly from the fire box to the smoke pipe l5'must alternately travel about the drum in opposite directions. It will thus be seen that the drum will be thoroughly heated and also the inner shell and air flowing upwardly through the drum and the outer air chamber will be heated to a high temperature.

When the furnace is in use, soot and ash dust collect upon the drum and the inner surface of the inner shell and at times a scale forms upon the drum. In order to remove the soot, ash dust, and scale there have been provided cleaners 21 and 28, the cleaners 21 being secured at their upper ends to the drum and the cleaners 28 being secured at their lower ends to the inner shell. Each of the cleaners 21 consists of an upright frame carrying tufts of bristles projecting outwardly therefrom for engaging the inner surface of the inner shell. Each cleaner 28 also has an upright frame formed with a bracket 29 which is secured to the inner shell and carries an upwardly extending arm 30. A scraper'3l which is in the form of a helical spring or a wire is secured at its upper and lower ends to the arm and the bracket and conforms to the contour of the portions of the drum engaged thereby.

In order that the cleaners may remove the dirt and scale from the inner shell and the drum, the drum must be turned about a vertical axis. Therefore, the drum has been mounted for rotary movement by providing the construction illustrated in Figures 1 and 6. Referring to these figures it will be seen that at its upper end the neck of the drum carries a spider 32 in the hub of which the lower end of a shaft 33 is secured. This shaft is journaled through a bearing 34 at the center of an upper spider 35 and carries a bearing cup 36 which rests upon bearing balls 31 provided so that the drum may turn easily. The upper portion of the shaft extendsoutwardly through a boss formed at the center of the cap or head 1 and carries a worm gear 38 meshing with a worm 39 carried by a shaft 40 which is rotatably mounted in bearings carried by the head and projecting outwardly therefrom to such an extent that the handle 4| of the hand wheel 42 may be easily grasped and rotary motion imparted to the shaft 40. When this actuating shaft is turned, rotary motion is transmitted to the drum and as the drum turns the scrapers 3| of the cleaners 28 will have scraping engagement with the walls of the drum to remove dirt and scale while the brushes of the cleaners 21 which move with the drum will have brushing engagement with the inner surface of the inner shell and dirt removed therefrom. This dirt and scale drops downwardly and lands upon the bafile plates or rings 26. The dirt and scale which lands upon the upper ones of the baffles will be removed therefrom by the brackets 29 of the cleaners 28 and that which lands upon the lower baffle will be engaged by a scraper'43 and scraped therefrom so that it drops into a box or drawer 44 which is slidably mounted in a chamber 45 at the bottom of the furnace. It will thus be seen that when the furnace is in operation, walls of the chamber be thoroughly heated as it moves upwardly towards the air pipes l0.

Having thus described the invention, what is claimed as new is:

1. In a stove, a drum defining an air chamber,

a shell about the drum providing a heating chamber, means for rotatably supporting said drum,manually operated means for rotating the drum, acleaner in said heating chamber secured at its lower end to said shell and extending vertically in .position for engaging the drum to clean the drum when the drum is rotated, and a second cleaner in the heating chamber secured at its up per end to said drum and extending downwardly in position for engaging the shell to clean the shell and moving between the shell and the first cleaner when the drum is rotated.

2. In a stove, a-drum defining an air chamber, a shell about said drum providing a heating chamber, means for rotatably mounting said drum, and a cleaner in said heating chamber carried by said shell and engaging the drum to clean the drum when the drum is rotated, said cleaner consisting of a bracket secured to the shell, an arm extending vertically from said bracket with its free end portion directed towards the drum, and a resilient scraper extending vertically with its ends secured to the bracket and the free end of the'arm and engaging the drum for cleaning the drum when the drum is rotated.

3. In a stove, a drum defining an air chamber, a shell about said drum providing a heating chamber, means for rotatably mounting said drum, a cleanerin said heating chamber carried by said shell and engaging the drum to clean the drum when the drum is rotated, and a cleaner in the heating chamber carried by said drum and engaging the shell to clean the shell when the drum is rotated, the cleaner for the drum being secured at its' lower end to the shell and including a resilient scraping "member conforming to the contour of the drum, and the cleaner for the shell being disposedvertically in the heating chamber between the shell and the cleaner for the drum and "having its upper end secured to the drum, the

last-mentioned cleaner being provided with tufts or bristles projecting laterally thereof for engaging the inner surface of the shell.

4. In a stove, a drum defining an air chamber open at its top, an inner shell'surrounding said drum and defining a heating chamber, an outer shell surrounding the inner shell and defining an air chamber, a head over said drum having depending walls engaging upper ends of the shells and formed with openings establishing communication between the head and the outer air chamber, said head being formed with discharge openings above the outer shell, said drum having its upper end rotatably engaged with walls of the head to rotatably support the drum, a spider carried by the upper end of said drum and provided with a stem extending upwardly and journaled through the head, an actuating shaft rotatably carried by said head and connected with the stem for imparting rotary motion to the drum when the shaft is rotated, and means in the heating chamber for cleaning the drum and the inner surface of the inner shell when the drum is rotated.

5. In a stove, a drum defining an air chamber open at its top, an inner shell surrounding said drum and defining a heating chamber, an outer shell surrounding the inner shell and defining an air chamber, a head carried by the upper ends of the shells and engaging the upper end of the drum to rotatably support the drum, said head having air passages opening into the air chamber between the shells and above the outer shell having discharge openings, annular bafile rings in the heating chamber spaced Vertically from each other and provided with air passages out of vertical alinement whereby the rings define a tortuous path through the heating chamber, cleaners for the drum and the inner shell mounted in the heating chamber and adapted to clean the drum and the inner shell when the drum is rotated, certain of said cleaners engaging the bafiles for removing dirt therefrom when the drum is rotated, and means carried by said head for rotating the drum.

JAMES A. LINDSAY. 

